【Oracle】-【SNIPED和KILLED】-SPINED和KILLED的session清理流程

@dbsnake大拿的一个示例：

SQL> show parameter limit
 NAME     TYPE  VALUE
 ------------------------------------ ----------- ------------------------------
 asm_power_limit     integer 1
 java_soft_sessionspace_limit     integer 0
 resource_limit     boolean TRUE
SQL> create profile idletime limit idle_time 1;
 Profile created.


 SQL> alter user bisal profile idletime;
 User altered.
SQL> conn bisal/bisal

From another session:
SQL> select status from v$session where username='BISAL';
 STATUS
 --------
 ACTIVE
 INACTIVE
After one minute:
SQL> select status from v$session where username='BISAL';
 STATUS
 --------
 ACTIVE
 SNIPED
From BISAL session:
SQL> select * from dual;
 select * from dual
 *
 ERROR at line 1:
 ORA-02396: exceeded maximum idle time, please connect again
From another session:
SQL> select status from v$session where username='BISAL';
 STATUS
 --------
 ACTIVE

验证一个SNIPED的session，重新执行一条SQL，Oracle会自动删除该session。

再做一个实验：

Conn bisal
From another session:
SQL> select status from v$session where username='BISAL';

 STATUS
 --------
 ACTIVE
 INACTIVE
SQL> select username,serial#, sid, to_timestamp(logon_time) from v$session
   2  where username='BISAL';

 USERNAME  SERIAL# SID            TO_TIMESTAMP(LOGON_TIME)
 ---------------------------------------------------------------------------
 BISAL 8  208                   10-JUL-13 12.00.00 AM
 BISAL       15 215                   10-JUL-13 12.00.00 AM
SQL> alter system kill session '215, 15';
 System altered.
SQL> select status from v$session where username='BISAL';
 STATUS
 --------
 ACTIVE
 KILLED
From BISAL session:
SQL> select * from dual;
 select * from dual
 *
 ERROR at line 1:
 ORA-00028: your session has been killed
From another session:
SQL> select status from v$session where username='BISAL';

 STATUS
 --------
 ACTIVE

即KILLED状态的session执行一个SQL，也会立即清除，这个据@eygle介绍是PMON负责的。"如果此时被Kill的process，重新尝试执行任务，那么马上会收到进程中断的提示，process退出，此时Oracle会立即启动PMON来清除该session.这被作为一次异常中断处理."